In recent years, dry-eye patients are increasing sharply in number in association with the indoor dryness ascribed to the spread of air conditioners, increasing operations of VDT such as personal computers, increasing number of contact lens users, and the diversity of changes in living and social environments. Dry eyes mean a state wherein the cornea and conjunctiva on the eyeball surface undergo a damage caused by the quantitative or qualitative abnormality of tear fluid. Tear fluid is constituted of three layers including an oil layer, an aqueous layer and a mucin layer. The tear fluid becomes unstabilized when the quantitative and qualitative balance of this three-layered structure is destroyed, so that the corneal disorder occurs, thereby bringing about dry eyes. In a dry-eye treatment, it is important to restore this three-layered structure of the oil layer, aqueous layer and mucin layer and to treat the corneal disorder.